Treatment of threads, fabrics, or other materials composed of or containing artificial filaments



Patented June 2, 1931 UNITED STATES PATENT OFFICE CHARLES WILFRED'ZPALMEB AND STEPHEN MILLER FULTON, OF SPONDON, NEAB DERBY, ENGLAND, ASSIGNOBS TO CELANESE CORPORATION OF AMERICA, A' COR- POBATION OF DELAWARE TREATMENT OF THREADS, FABRICS, OR OTHER MATERIALH OOM'POSED OF OR CONTAINING ARTIFICIAL FILAMENTS Io Drawing. Application filed November 16, 1925, Serial 110. 69,526, and in Great Britain Kay 28, 1925.

ficial silk made from cellulose acetate solutions of relatively low concentrations, is subjected to the action of hot or boiling solutions of acids or acid salts or hot or water, particularly water between about 90 cellulose acetate artificial silk can lose its nat- .ural high lustre to a greater or less extent and become converted to a more or less delustred condition.

The application of processes in which such delustring of cellulose acetate artificial silk occurs, for the production of threads or goods showing the efiects of wool, hair or other modified effects, forms the subject of U. S.

25 Patent No. 1,554=,801, according to which lustrous cellulose acetate filaments or threads, or goods containing the same, are subjected to the action of agents whereby the cellulose acetate filaments or fibres are delustred to any desired extent and more or less crinkled. The filaments or fibres of cellulose acetate resulting from such treatment of said patent are in fact hollow filaments, due probably to the action of the delustring and crinkling agents Further, artificial silks spun from cellulose acetate solutions of high concentrations, e. g. containing from 20' to 25 or 30% or more of oiling in releasing in or from the filaments residualcellulose acetate,are notso liable to becomedelustred as those produced from less concentrated solutions containing for example under about 10% or up to about 16 or 18% of cellulose acetate. Delustring may, however, occur even wit very resistant qualities of cellulose acetate artificial silk under the prolonged or especially intensive action of said agencies.

The object of the present invention is to provide means for preventing or controlling to any desired degree the delustring of cellulose acetate artificial silk caused by water or solutions, especially hot or boiling water or steam or other aqueous agents or media. By means of the invention, the lustre of the acetyl cellulose threads or filaments exposed to such delustring agencies may be preserved wholly or may be modified to any desired degree according to the technical eflt'ect desired.

We have found that the presence of one or; more protecting agents or substaiices restrains, retards or even prevents the delustring action of such agencies. The presence of such protecting agents or substances enables any desired degree of protection of lustre to be afforded according to the protect.- ing agent or substance used, the concentration thereof and the nature and duration of exposure to the aqueous media. Any agents having the desired protectin' action may be employed for the purpose 0 the invention. Protecting agents we have found useful for the purpose of the invention comprise nearly all soluble salts, especially normal salts, and preferably readily ionizable neutral salts, or

similarly acting substances such as the sugars, v I

1. C. and the boiling point, or moist steam, solutions, particularly acid solutions, moist 55 versely as the molecular weight. Thus ammonium or lithium salts are most effective, followed by the corresponding salts of sodium, potassium, magnesium, aluminium and so forth. As previously stated the use of neutral salts is preferred, though'salts having an acid reaction may also be employed.

Substances such as cane sugar and the like are not so powerful in their protective action as are many of thesalts: thus for example the presence of 0.6 to 1% ammonium sulphate or protecting agent employed and the concentration thereof, the nature and temperature of the bath and the duration of the treatment. .Thus for example only a slight degree of delustring is roduced on subjecting cellulose acetate arti cial silk to a 5% boiling solution of cane sugar for about 10 minutes or a 20% solution of sodium chloride for about 30 minutes, the resultant product in these cases having a lustre approaching that of real silk, while the lustre is substantially unchanged on boiling cellulose acetate artificial silk for about one hour with a 5% solution of am monium sulphate or sodium sulphate.

For preventing or controlling the delustring action of moist steam we may apply the protecting agents or substances to the goods in any suitable manner.- For example the goods may be soaked in aqueous solution of the protecting agent, for instance ammonium sulphate, prior to exposure to the moist steam, the goods being dried prior to exposure if desired.

The present invention affords valuable technical advantages in that it allows of preventing entirely or of regulating to any desired degree the delustring of goods consisting of or containing cellulose acetate artificial silk under the action of delustring agencies to which such goods are exposed in various processes or treatments to which they are commonly subjected in industry, for example dyeing, crping, crabbing, steaming, scouring and so forth. Especially we have found that the retarding or restraining influence of the protecting agents is particularly useful with regard to mixed yarns, fabrics or materials containing cellulose acetate artificial silk associated with wool or other fibres. It is often necessary to subject such mixed goods, particularly mixed goods containing wool and cellulose acetate artificial silk, to the action of hot or boiling baths and such treatoften for considerable time, to effect the dyeing of the wool, and in such cases the cellulose acetate artificial silk may be partially or often totally delustred. We have found that the lustre of the cellulose acetate artificial silk can in such cases be protected or controlled to any desired degree by the presence of one or more of the protecting agents in the hot or boiling baths. Thus for example in dyeing mixed goods composed of cellulose acetate artificial silk and wool, the presence of a protective salt such as referred to in the dye bath used for dyeing the wool portion, will allow of preventing or regulating the delustring action of thedye bath as required: for instance as little as 20% relatively to the weight of the goods, of a salt such as ammonium sulphate will preserve the lustre of the cellulose acetate according to requirements.

It will be seen that the invention provides means not only of preventing partial or complete delustring o the cellulose acetate filaments etc. under the action of delustring agencies, but also of controlling or regulating the degree of partial or complete delustring to any desired-extent, which is of advantage in many technical aspects. For example it is thus possible to modify the lustre to resemble that of natural silk or other fibres or to any other desired degree for particular effects.

It will also be understood that not only can the invention be employed for preventing or regulating delustring of cellulose acetate artificial silk wholly or to any desired de rec in processes or treatments to which goods consisting of or containing it are normally exposed in industry (e. g. dyeing, creping, crabbing, steaming, scourin and so forth),

but thatv the invention can a so be applied as -or other protective agents as referred to. The

term materials as used in the claims is to be interpreted as including threads, fabrics and other goods.

The phrase hot aqueous medium is used in the appended claims to include hot or boil ing aqueous liquids, particularly such liquids as have a temperature of 90 C. or over, or moist steam, whether such agents are used alone or in conjunction with other agents used in technical operations such as dyeing, creping, crabbing, steaming, scouring, and so forth.

What we claim and desire to secure by Letters Patent is 1. In a process of treating a material containing lustrous cellulose acetate filaments with an agent which tends to delustre the material, conducting the treatment in the presence of a normal salt of neutral to acid reaction. 1

2. In a process of treating a material containing lustrous cellulose acetate filaments with a hot aqueous medium which tends to delustre the material, conducting the treatment in the presence of a normal salt of neutral to acid reaction.

3. In a process of treating a material containing lustrous cellulose acetate filaments with a hot aqueous medium which tends to delustre the material, conducting the treatment in the presence of a lustre protecting agent comprising a water soluble normal salt of neutral to acid reaction dissolved to form a solution of a concentrationefiective to preserve the lustre of said'materials at least in part.

4. In a process of treating a material containing lustrous cellulose acetate filaments with a hot aqueous medium which tends to delustre the material, conducting the treatment in the presence of a lustre protecting agent comprising a readily ionizable normal salt of neutral to acid reaction, dissolved to form asolution of a concentration effective to preserve the lustre of said materials'at least in part.

5. In a process of treating a material containing lustrous cellulose acetate filaments with a hot aqueous medium which tends to delustre the material, conducting the treatment in the presence of ammonium sulphate.

6. A process for treating a material containing lustrous cellulose acetate filaments for the purpose of modifying its lustre, which consists in submitting the material to the delustring action of a hot aqueous medium in the presence of a lustre-protecting agent in a proportion lower than that necessary for maintaining the original lustre.

7. A process for treating a material containing lustrous cellulose acetate filaments for the purpose of modifying its lustre, which consists in submitting the material to the action of a hot aqueous liquid in which is dissolved a lustre-protecting agent to form a solution of lower concentration than that necessary for maintaining the original lustre. v

8. A process for treating a material containing lustrous cellulose acetate filaments for the purpose of modifying its lustre, which consists in submitting the material to the action of a hot aqueous liquid in which is dissolved a lustre-protecting saline agent to solved a lustre-protecting agent comprising a normal salt of neutral to acid reaction to form a solution of lower concentration than that necessary for maintaining the original lustre.

10. A process for treating a material containing lustrous cellulose acetate filaments for the purpose of modifying its lustre, which consists in submitting the material to the action of a hot aqueous liquid in which is dissolved a lustre-protecting agent comprising ammonium sulphate to form a solution of lower concentration than that necessary for maintaining the original lustre.

In testimony whereof we have hereunto subscribed our names.

' CHARLES WILFRED' PALMER.

STEPHEN MILLER FULTON. 

